Dion did not elaborate on Twitter, but the minister's office said he is concerned about past statements Lynk has made, noting that the Ontario professor would have applied on his own to be a UN Special Rapporteur.

"They are not nominated by their states and anyone can apply directly to the UN; this candidate was not put forward by Canada and does not represent the views of this government," Dion's office said in an emailed statement.

The statement also said Canada's UN ambassador made it clear the human rights council should appoint a "professional, neutral and credible" candidate.

Lynk did not immediately respond to an email about Dion's concerns.

He said on Thursday that he was aware of the controversy around his appointment but contended that his writings and views were being misrepresented.

The professor declined further comment but said he would speak further once he had the chance to confer with the UN over the details of his new position.

Lynk said he was delighted to be chosen for the role and would carry out his responsibilities impartially and in keeping with international law.

Clement called on Prime Minister Justin Trudeau to apply pressure against Lynk's selection by the president of the UN Human Rights Council.

He said in a statement that Lynk has called for the prosecution of Israel for war crimes.

The UN's website says a special rapporteur's job is to examine and report back on the human rights situation in a specific country or a specific human rights theme. The position is honorary and the appointees are not paid or UN staff.